< 
Fig. 26. Profile view of sam 
Fig. 3. Pygidium of 
258 W. B. Dwight—Fossils of the Wappinger Valley. 
From the above mentioned position of maximum ventri- 
cosity in the chamber of habitation, the shell diminishes with 
a rapid taper posteriorly to the apex. At the distance, how- 
ever, of eight or nine septa from the first one, the rate of taper, 
which up to that point has been as one to three, diminishes a 
- little for the remaining apical portion, causing a slight concay- 
ity in 15 outline in that vicinity. 
made across this fossil 4™ anterior to its posterior 
termination, reveals one (dorsal ?) half of the transverse section 
and shows that the complete section must be a little elliptical 
(if not = The siphuncle, which is shown in this section 
near the end of the longer axis of this semi-ellipse, is very 
small, with a diameter of *65™" where the shell has a diameter 
of 6™™; it is circular and quite close to the shell, though not 
actually in contact. The septa are frequent, about twenty- 
three to the inch, two or three nearest the chamber of habita- 
_ snes much closer together. ney are nee Liste 
tained in the cross-cut of Sie: position of the eee removes 
all doubt that it is a distinct species. It is certainly no nearer 
to O. constrictum Hall, and appears to be new. 
EXPLANATION OF PLATE VII.—WAPPINGER VALLEY FOSSILS. 
e specimens here illustrated are — the Calciferous (?) at Rochdale, 4 
All 
N. Y., and are represented in their natural siz 
BATHYURUS i TAURIFRONS. 
Fig. 1. Glabella and fixed cheeks, the ormer showing the furrows and median 
ng t 
gular line. The furrows apa r much too conspicuous in the cut. 
Fig. la, Profile view of the same s 
pecimen. sane a 
Fig. 2. A pygidium found in close pro | » the above, probably of the 
species, if not of the same indivi 
verse contour of the enteror 
@ pygi 
another fadividaal of same species, showing distinctly the 
two posterior es on the axis. ; 
% 
_ Fig. 2a. Vertical transverse section of the ae: " showing the elevation and — | a 
limb. . 
